Knife serrating device



G. D. SILBERMAN KNIFE SERRATING DEVICE 'May 3o, 1967 Y Filed Nofv. 25, 1954 INVENTOR..

United States Patent O 3,322,002 KN'IFE SERRATING DEVICE Glenn D. Silberman, deceased, late of Muncie, Ind., by

Margaret M. Silberman, admiuistrahix, Ha'll,

Buckles and Stern, 108 E. Washington St., Muncie,

Ind. 47305 Filed Nov. 23, 1964, Ser. No. 413,371 4 Claims. (Cl. 76-89.1)

This invention relates to a knife serrating device for forming a serrated edge on a knife, particularly a steak or other table knife.

It is an object of the invention to provide a serrating device which will be conveniently usable to form and sharpen serrated edges on knives, and especially on table knives such as steak knives, and which is adapted to receive variously shaped knives and to serrate the shaped edges of such knives. It is a particular object of the invention to provide a knife serrating device adapted to operate on conventional table knives having elongated cutting edges which curve upward toward a tapered point, and which will be conveniently eective to serrate the upwardly curved cutting portion of the edge where much of the cutting action occurs in normal use of such knives. It is a further object of the invention to provide such a knife serrating device which can be largely composed of and driven by a standard motor and gear components; which will be sturdy and provide ample bearing support for the cutter blade without imposing undue stress on the bearings of the standard motor and gear components, which will be simple, safe, and reliable in use, and in which the cutting action will tend to progress along the cutting edge of the knife and may be made to follow the shape of such edge.

In accordance with the invention, the knife serrating device desirably comprises a cutter housing having a pair of adjoining faces, such as front and Itop faces, through which an elongated knife-receiving slot is cut to receive edgewise a knife to be serrated, The cutter housing may be fixed to a drive housing from which a slow-speed output shaft extends parallel to and olset from the knife slot. A cutter wheel having a peripheral cutting face is mounted coaxially with the output shaft, in forwardly spaced relation from the drive housing, and is supported from the cutter housing by a closely adjacent bearing. The cutting ,face intersect the knife slot in such relation that the plane of the slot extends chordally of the cutter wheel. Both in front of and behind the cutter wheel for a substantial distance, the bearing means and cutter drive means are positioned and arranged to clear the knife slot at the level of such intersection, and desirably for va distance below such level, to allow free movement of differently shaped knife edges. The cutting face of the cutter wheel carries helically arranged cutting teeth which tend to progress along the edge which they are cutting, so that they tend to feed the knife lengthwise of itself, and the helix is arranged to cause such feeding to feed the knife out of the slot. f

The cutter Wheel is desirably mounted in xed relation on the drive shaft and is enclosed and supported by the cutter housing, and such housing is removably mounted to the drive housing. The Cutter housing is desirably a metal casting formed with a cavity to surround the cutter wheel and with a closely adjacent bearing seat.

Preferably, the bearing seat is outward of the cutter cavity,

and the main bearing for the cutter shaft is outboard of the cutter. This not only provides close support to the cutter wheel at some distance from the shaft bearing in the drive housing, but also permits the cutter housing to wholly enclose the cutter wheel while still providing desirable clearance along the slot for variously shaped knife edges, and permits the enclosing cutter housing to be forwardly removable from the cutter and shaft assembly.

The accompanying drawings illustrate the invention. In such drawings:

FIG. 1 is a perspective view of a knife serrating device embodying the invention, and showing a knife being serrated thereby;

FIG. 2 is a side elevation of the device shown in FIG. 1, with the cutter housing shown in section; and

FIG. 3 is a section taken on the line 3 3 of FIG. 2.

The embodiment shown in the drawings comprises an assembly of a cutter housing 10, a gear housing 12, and a motor housing 14, xed together and mounted on feet 15. The gear housing contains a gear reduction set (not shown) having an input shaft connected to a motor 16 mounted in the housing 14 and supplied with electric current through a cord 1S, under control of a switch 20. The motor 16 and the gear reduction set contained in the gear housing 12 are of conventional construction and a standard commercial type.

The gear set has an output shaft 22 journalled in the gear housing 12 and projecting from the front face thereof, which is driven at cutting speed, say of the order of 60 r.p.m. A sleeve coupling 24 is coaxially fixed on the shaft 22, as by means of a set screw 26, and carries at its forward end a cutter shaft 28, fixed in the coupling 24 as by a cross pin 29. A cutter wheel 30 is lixed on the cutter shaft 28, and the shaft extends forwardly therefrom into the inner race of a ball bearing 32, positioned closely adjacent the front face of the cutter wheel 30 and supported by the cutter housing 10.

The cutter housing is a box-like casting having rearwardly extending Walls in abutment with the front face of the gear housing 12, and is bolted to the gear housing by bolts 34. The front wall 36 of the cutter housing is of thick section and is bored from the rear to provide a recess 40 for the cutter wheel 3o and a recess 38 to snugly receive the outer race of the ball bearing 32. A vertical bore 42 extends downward from the bottom of the cutter recess 40 to form a chip discharge chute.

The front wall 36 and top wall 37 of the cutter hous- 'ing 10 are cut to form a knife receiving slot 44 in a plane which is olf-set from the shaft axis and intersects chordally the cutter wheel 30. The knife slot 44 extends the full length of the cutter housing, which itself is long enough to provide adequate slot length. The slot is open and unobstructed both upwardly through the top wall of the housing 10 and forwardly through the front wall of the housing 10, and the plane of the slot is unobstructed so that knives maybe manually inserted edgewise downward into the slot and are freely moveable vertically, length- Wise, and tilta'bly in the slot.

The cutter wall 30 has a peripheral cutting face provided with helically-arranged cutter teeth adapted to cut spaced ser-rations in the edge of a knife Sti held against the cutting face. As shown in FIG. 3, the cutter wheel rotates in a direction, counterclockwise as shown, which carries its cutting face downwardly across the slot 44, to produce a transverse and downward cutting on a knife blade held in the slot. The helical arrangement of the teeth tends to feed the knife 50 lengthwise of the cutter as the cutting proceeds, and the helix hand and the direction of cutter rotation are such that the knife is fed forward in the slot and the cutter wheel progresses toward the point of the knife.

The cutter wheel 30 is larger than lthe bearing 38 and the coupling 24, and its peripheral cutting face intersects the plane of the slot 44 at a level which is above the bottom of the slot and above any projection of the bearing and coupling into the plane of the slot. In consequence, both the front and rear portions of the slot are clear not only upwardly and forwardly of such intersection serrated, and the lengthwise position of the -blade is adjusted accordingly so that the cutter initially engages a mid point of the blade where the serration is to start. The knife is manually pressed downward into the notch between cutting face of the cutter wheel 30 and the side wall of the notch, and simply held in such engagement. The wheel 30 cuts separated serrations in the knife edge and feeds the knife lengthwise, forwardly out of the slot. As the knife moves forward and the cutter progesses along the knife edge, the knife handle is progressively raised toY A tilt the blade appropriately to cause the cutting action to follow the curved edge of the lblade, as indicated in dotted lines in FIG. 1. Serrations are desirably cut along the entire front end of the blade, and especially along the upward curving front edge of the blade leading to the point. The lfreedom Yof manual movement of the knife in the slot'permits variously shaped knives to be serrated over this entire front edge portion.

What is claimed is: 1. A knife serrating device, comprising a cutter housing having adjoining top and end faces and forming an elongated narrow slot open through the top face and one end face for t-he downward edgewise reception of the forward end portion of a knifefblade Vto be serrated, a drive housing fixed to an output shaft journalled therein and'extending parallel to and offset from said slot, a motor connected to drive said shaft at cutter speed, motor housing means, said cutter, drive, and motor housings forming a substantially continuous elon- Y gated protective enclosure about the cutter, drive, and motor,rwith saidrslot extending longitudinally at one end of saidv enclosure,

the cutter housing and having a cutter wheel spaced forwardly from said drive housy ing, mounted coaxially with said output shaft, and supported :by a closely-adjacent bearing in said cutter housing, Y p

said Ycutter wheel having a peripheral cutting face Yintersecting said knife slot with the plane of the extending chordally of the cutter wheel,

saidscutting face comprising helically-arranged cutting teeth which Vtend to progress'rearwardly of the slot along the edge of a knife being serrated and thereby to `feed the knifelengthwise forwardly out ofthe slot, Y

the side walls of said slot providing knife supporting faces -to hold the knife substantially in a vertical chordall plane with respect to the cutter wheel and the slot being clear and unobstructed forwardly, upwardly, and for a distance rearwardly of said intersection, Y f

whereby any of various shapes and sizes of knives can be manually inserted edgewise into the slot and into cutting engagement with the cutter face and can be manually pressed into said upwardly open slot, will be laterally supported thereby, and may 'be tilted as needed to cause the cutter teeth to feed themselves along and follow the shaped edge of the knife to serrate such shaped edge.

2. A knife serrating device according to claim 1 with the addition that said cutter bearing and the cutter drive means are positioned to clea-r the knife slot for a distance below the intersection therewith of the cutter face.

3. A knife serrating device according to -claim 1 in which said cutter wheel is fixed to said output shaft and said cutter-supporting bearing is in front Vof said cutter,

said cutter housing comprises a formed casing having a rearwardly open cavity to receive and enclose the cutter wheel, with a discharge chute extending downward therefrom,

and having a second recess in front of the cutter wheel recess to receive and support the cutter-supporting bearing, and said cutter housing is removably mounted assembly to and from said drive housing. 4. A knife serrating device comprising Y a drive housing having a drive shaft j and extending forward therefrom,

-power means to drive said shaft,

a cutter wheel tixedly mounted on said drive yshaft and spaced forward from t-he drive housing, an outboard shaft bearing on the cutter shaft closely in front of said cutter wheel,

a front cutter houslng wall axially assembled toward and removably fixed to said cutter housing and recessed to receive and support said outboard shaft.-Y

bearing and enclose said cutter wheel, Y said cutter wheel having a peripheral cutting face provided with helically-arranged cutting teeth adapted to serrate and feed forwardly a knife blade held in cutting engagement therewith, and a knife-supporting face on said cutter housing wall in a plane chordally and defining with the face thereof a downwardly converging cutting notch, said face being the face of a knife-receiving slot formed in the cutter housing,

said slot being open and unobstructed upwardly andV Y forwardly of, and for a distance rearwardly and Y Y downwardly of, the cutting notch,

the knife-receiving plane of said notch beingrclear and unobstructed upwardly and axially of said intersection, `for the downward. edgewise reception of a knife blade therein and for free forward and tilting movement thereof yas the feeding action of the cutter.

wheel feeds the blade Iforward of lthe cutter.

References CitedV Y UNITED STATES PATENTS 2,444,110 6/ 1948 Pavesi et al. 76'-88 2,623,416 12/1952 Sasse 76-8,9.1 2,673,477 Y 3/1954 YDavis 76-89.1 2,713,236 7/ 1955 Gross.

GRANVILLE Y, VCUsrER, JR., Primary Examiner.

for axial ournalled therein intersecting said cutter wheel 

1. A KNIFE SERRATING DEVICE, COMPRISING A CUTTER HOUSING HAVING ADJOINING TOP AND END FACES AND FORMING AN ELONGATED NARROW SLOT OPEN THROUGH THE TOP FACE AND ONE END FACE FOR THE DOWNWARD EDGEWISE RECEPTION OF THE FORWARD END PORTION OF A KNIFE BLADE TO BE SERRATED, A DRIVE HOUSING FIXED TO THE CUTTER HOUSING AND HAVING AN OUTPUT SHAFT JOURNALLED THEREIN AND EXTENDING PARALLEL TO AND OFFSET SAID SLOT, A MOTOR CONNECTED TO DRIVE SAID SHAFT AT CUTTER SPEED, MOTOR HOUSING MEANS, SAID CUTTER, DRIVE, AND MOTOR HOUSINGS FORMING A SUBSTANTIALLY CONTINUOUS ELONGATED PROTECTIVE ENCLOSURE ABOUT THE CUTTER, DRIVE, AND MOTOR, WITH SAID SLOT EXTENDING LONGITUDINALLY AT ONE END OF SAID ENCLOSURE, A CUTTER WHEEL SPACED FORWARDLY FROM SAID DRIVE HOUSING, MOUNTED COAXIALLY WITH SAID OUTPUT SHAFT, AND SUPPORTED BY A CLOSELY-ADJACENT BEARING IN SAID CUTTER HOUSING, SAID CUTTER WHEEL HAVING PERIPHERAL CUTTING FACE ININTERSECTING SAID KNIFE SLOT WITH THE PLANE OF THE EXTENDING CHORDALLY OF THE CUTTER WHEEL, 